Outdoor speaker enclosure

ABSTRACT

An outdoor speaker enclosure comprising a box enclosing a loudspeaker, or a plurality thereof, opening outwardly of said box, and a cover for the speaker opening specially formed to resist the entry of moisture therethrough but being porous to permit the unobstructed egress of sound therethrough, said box having specially formed vents providing both for effective ventilation of the box interior and also for improving the sound reproduction quality of the speaker.

United States Patent [1 1 3,674,108 Beatty 14 1 July 4, 1972 541 OUTDOORSPEAKER ENCLOSURE 2,556,168 6/1951 Cragg et al ..1s1/31 A 2,588,0863/1952 Cole ....l81/3l B X [721 Invent 1"? MW, 4832 Adams Shawnee3,141,070 7/1964 Schenkel et a1 ..179/121 D x M1ss1on, Kans. 6.6205

[22] Filed: Oct. 29, 1970 Primary Examiner-Stephen .l. TomskyAttorney-John A. Hamilton [21] Appl. No.: 85,199

[57] ABSTRACT [52] US. Cl ..181/31 B An outdoor speaker enclosurecomprising a box enclosing a [51] Int. Cl. ..G10k 13/00, l-l04r l/28loudspeaker, or a plurality thereof, opening outwardly of said [58]Field of Search ..181/31 A, 31 B, DIG. 1; and a cover for the speakeropening specially formed to 179 1 4 resist the entry of moisturetherethrough but being porous to permit the unobstructed egress of soundtherethrough, said 56] References Cited box having specially formedvents providing both for effective ventilation of the box interior andalso for improving the UNITED STATES PATENTS sound reproduction qualityof the speaker.

2,210,477 8/1940 Benecke et al ..l8 1 [31 B 8 Claims, 5 Drawing FiguresOUTDOOR SPEAKER ENCLOSURE This invention relates to new and usefulimprovements in speaker enclosures for radio, high-fidelity, andstereophonic sound reproduction systems, and has particular reference tospeaker enclosures intended for usage outdoors, as on patios, porches,and the like, where they are necessarily exposed to the weather at leastto some degree.

Exposure to the weather, particularly to rain, snow, dew, condensation,and other moisture, creates certain problems in connection with speakerenclosures. The enclosure must of course be supported by some meansproviding that the enclosure itself cannot directly engage anysupporting surface on which moisture can collect, and from which itcould seep into the enclosure. The speaker itself must be protectedagainst rain or other moisture, even when said rain may be driven by ahigh wind. At the same time, the speaker opening of the enclosure shouldnot be covered by any completely non-porous, waterproof layers, as thesewould mufile and otherwise reduce the quality of the sound reproduced bythe speaker. Also, the enclosure itself should be well ventilated toprovide for the disposition of any moisture which may find its waytherein, or which may form therein by condensation due to substantialtemperature changes in the surrounding air.

Accordingly, the object of the present invention is the provision of anoutdoor speaker enclosure which fulfills all of the above enumeratedrequirements, in a novel, efficient manner. The present invention, tothis end, involves two principal innovations. First, the speaker openingof the enclosure is provided with a special covering formed in a novelmanner to resist the passage of rain or other moisture therethrough,while at the same time permitting passage of air therethrough withsufiicient freedom not to muffle or otherwise detract from the qualityof the sound reproduced by the speaker. Generally, this is accomplishedby a cover including a plurality of spaced apart layers of cloth ofsuccessively greater resistance to the passage of water therethrough,and the provision of means for draining away any moisture from thespaces between said layers.

Second, there are provided special vents or openings for ventilating theenclosure. Speaker enclosures are already often provided with vents forthe purpose of allowing the escape of sound generated in the enclosurefrom the inside of the speaker cone. Such vents thus cause the enclosureto act as a sounding box for the speaker, and have been found quiteeffective in strengthening and reinforcing the bass notes or otherlow-frequency sounds reproduced by the speaker. However, such vents haveheretofore not been so arranged or disposed either to inhibit the entryof moisture into the enclosure, or to provide for circulatoryventilation of the interior thereof. The present invention provides forthe formation and disposition of the vents whereby to perform theseadditional functions.

Other objects are simplicity and economy of construction, and efficiencyand dependability of operation.

With these objects in view, as well as other objects which will appearin the course of the specification, reference will be had to theaccompanying drawing, wherein:

FIG. 1 is a front elevational view of an outdoor speaker en closureembodying the present invention,

FIG. 2 is a sectional view taken on line II-II of FIG. 1, with partsleft in elevation,

FIG. 3 is a sectional view taken on line III-III of FIG. 2,

FIG. 4 is a sectional view taken on line IV-IV of FIG. 2, with partsleft in elevation, and showing a slight modification of structure, and

FIG. 5 is an enlarged, fragmentary sectional view taken on line V-VofFlG. 1.

Like reference numerals apply to similar parts throughout the severalviews. The speaker enclosure forming the subject matter of the presentinvention includes a body member which may be fonned of wood or anyother suitable material, and may have the form of a generallyrectilinear box, having a floor 2, left and right side walls 4 and 6,rear wall 8, front wall 10, and a top wall consisting of two inclinedpanels 12 and l4 whereby to form a peaked roof to better shed rain andthe like, all of said members being rigidly connected together by anysuitable means, not shown, whereby to form a unitary structure. Theenclosure is supported above any supporting surface 16 by short legs 18affixed thereto at each of its four comers. Roof panels 12 and 14 areextended outwardly to form eaves overhanging all of the front, rear, andside walls of the enclosure, and front wall 10 is recessed inwardly fromthe forward edges of side walls 4 and 6. A circular speaker opening 20is formed in front wall 10, and a speaker 22 is affixed in said openingas by bolts 24, whereby to direct sound reproduced thereby forwardlyfrom the enclosure. The speaker includes a speaker cone (not shown)coaxial therewith, which generally seals opening 20 of front wall 10,and which is vibrated by speaker coil 26 to generate sound. The rearwardface of said cone is exposed to the interior of the enclosure throughopenings 28 formed in the speaker frame, so that vibration of the conealso vibrates the air within the enclosure. The necessary electricalconnections to the speaker may be made by any suitable means, not shown.

The forward surface of front wall 10, of course including speakeropening 20 and the speaker 22 mounted therein, is covered by aprotective panel indicated generally by the numeral 30. As best shown inFIGS. 1, 2, 4, and 5, said panel includes three planar, open frames 32,34 and 36, formed of wood or other suitable material, assembled inoverlying, coextensive relation to form a single composite frame.Overlying the outer or forward face of forwardmost frame 32 is a sheet38 of stout, relatively coarse textile fabric. The material of sheet 38should be of material sufficiently strong to resist damage by thephysical scratching, gouging, and the like to which it may be subjectedin outdoor usage, and is preferably formed of a synthetic material toresist damage by mildew and the like. Synthetics of the type and weightcommonly used for outdoor carpeting has been found satisfactory. Watermay pass through material of this sort with relative ease, and sheet 38would hence not, of itself alone, adequately protect speaker 22 againstmoisture.

Panel 30 also includes two sheets 40 and 42 of a very closely wovenmoisture-repellent textile fabric overlying the entire area of thepanel, the edges of sheets 40 and 42 being clamped respectively betweenframes 32 and 34, and between frames 34 and 36, whereby textile sheets38, 40, and 42 are supported in closely spaced apart, parallel relation.A closely woven nylon fabric, such as is commonly used as a tentingmaterial, has been found satisfactory for use in sheets 40 and 42.Coarse front sheet 38 is folded rearwardly around the edges of panel 30and secured to the rearward surface thereof as by tacks 44 (see FIG. 5).Panel 30 is secured bodily against the forward surface of frontenclosure wall 10 by screws 46. Referring to FIG. 5, it will be seenthat the upper edge of the lower horizontal leg 32A of frame 32 isinclined forwardly and downwardly as indicated at 48, and that centralframe member 34 has no horizontal lower leg at all, thereby providing anopening 50 between textile sheets 40 and 42 extending all the way to theextreme lower edge of panel 30. These latter provisions are for thepurposes of drainage, as will appear. The upper edge of panel 30 isprotected by the eaves formed by roof panels 12 and 14, and the verticalside edges of said panel are protected by their inclusion between theportions of side walls 4 and 6 projecting forwardly of front wall 10(best shown in FIG. 2), so that water cannot work around the edges ofthe panel.

Also provided are a pair of vent tubes 52 and 54. As shown, said tubesare elongated and of rectangular cross-sectional contour, tube 52 beingaffixed vertically to the inner surface of side wall 4, opening at itsupper end into the'enclosure and having its lower end disposed inregistry with a hole 56 fonned in floor 2 with a screen 58 interposedtherebetween to prevent the entry of insects into the enclosure. Tube 54is afiixed to the inner surface of roof panel 14, with its upper endopening into the enclosure and its lower end registered with a hole 60formed in side wall 6 beneath the eave formed by said roof panel, with ascreen 62 interposed therebetween.

In operation, it will be seen that rain or the like can pass withrelative ease through the coarse textile sheet 38 forming the outerlayer of protective panel 30 covering'the speaker. However, sheet 38does prevent the passage of much of the moisture, and furthermoreabsorbs much of the force of any wind which may be driving the rain,damping and reducing the air flow to the extent that any moistureentering between sheets 38 and 40 impinges against sheet 40 with muchless force, and in much smaller quantities, than it originally engagedsheet 38. This together with the additional fact that sheet 40 (and 42)is formed of a very closely woven, moistureshedding cloth such as nylontenting material, results in fact that very little water ever passesthrough sheet 40, and virtually none through sheet 42. Any watercollecting between sheets 38 and 40 drains outwardly through sheet 38 byreason of the bevel 48 of frame 32 at the lower edge of the spacebetween these sheets, and any water collecting between sheets 40 and 42drains downwardly through opening 50 formed by the elimination of thebottom leg of frame 34. The lower end of opening 50 is covered by sheet38, but water can pass therethrough easily, thus the speaker isprotected from rain or other moisture, while there are still airpassages through the panel as are necessary for the efficientundistorted transmission of sound therethrough. Panel 30 is sufficientlyeffective that even when a stream from a garden hose is directedthereagainst with full force, substantially no water passes throughinner sheet 42 thereof. This is a far more rigorous test than the panelwould be required to withstand in any normal usage.

At the same time, the enclosure is continuously ventilated, to evaporateand carry away any moisture which may for example form therein bycondensation, by air entering therein through tube 52, circulatingthrough the interior thereof, and leaving through tube 54. As previouslydiscussed, the venting of speaker enclosures for the acoustical purposeof strengthening and reinforcing low-frequency sounds is not new. Venttubes 52 and 54 also perform this function. However, such prioracoustical venting has ordinarily been performed by a single vent notadapted to perform the circulatory ventilation required in an outdoorenclosure. The present structure supplies this lack of prior structuresby dividing the vent into two sections disposed respectively adjacentthe bottom and top of the enclosure, whereby to promote air circulation,by disposing the atmospheric ends of the openings in protected zones toat least inhibit the entry of wind-driven rain therein, and by theprovision of tubes 54 extending upwardly inside of the enclosure fromthe atmospheric openings. These tubes virtually preclude the entry ofany water into the enclosure through the vents, in any normal usage. Thequality of the sound emanating from the vents is improved further by theprovision of means preventing reflection, or reverberation, of soundbetween opposite interior walls of the housing. For this reason, floor2, left side wall 6 and back wall 8 of the enclosure are provided withlinings 64 consisting of slabs of soundabsorbing acoustical material.

FIG. 4 shows a structural modification supplying an altemative, oradditional, means of venting the enclosure, consisting of short tubes 66and 68 affixed in openings provided therefor in front wall of theenclosure, respectively above and below speaker 22, but both behindprotective panel 30 covering the front of the enclosure. These tubesprovide for circulation of air through the enclosure, as do tubes 52 and54, and are protected against the ingress of moisture therethrough bypanel 30, in the same manner that said panel protects speaker 22. Theuse of tubes 66 and 68, rather than simply holes formed in front wall10, is dictated by acoustical considerations with which this inventionis not directly concerned, it having been found that tubular ventshaving certain proportions of length and cross-sectional contoursproduce better sound efi'ects than others. These considerations applyalso to the design of tubes 52 and 54. While tubes 66 and 68 have theadvantage of being simpler and cheaper to install than tubes 52 and 54,they are less efiicient for the purposes intended than tubes 52 and 54.Hence, while the two sets of tubes may be used either alternatively orconcurrently, the use of tubes 52 and 54 is preferable if only one setis used. The lack of efficiency of tubes 66 and 68 arises from the factthat protective panel 30, while necessarily permeable to some degree tothe flow of air therethrough, nevertheless still imposes considerablerestriction to air flow therethrough. This restriction has little effecton high-frequency sounds, since the physical volume of air displaced bythe speaker in high-frequency sound is very small, and very little airmust be forced through the panel. However, with sounds of very lowfrequency, which emanate principally from the vents, large quantities ofair are moved, resulting in quite noticeable inward and outward puffing"of air through the vents. Hence, any substantial restriction of the flowof air through the vents results in mufiling of the sound, so that thesubstantially unrestricted vents 52 and 54 are preferable. The flowrestriction provided by panel 30 also inhibits the free circulatoryventilation of air desired in the present case for drying purposes.While the use of tubes 52 and 54, opening through the bottom and side ofthe enclosure, causes the lowfrequency sounds to be initially directedin directions different from the axis of speaker 22, this is notdisadvantageous. While high frequency sounds are directional incharacter, making it desirable to aim the speaker toward a desiredlistening area, low frequency sounds are more pervasive andnon-directional in character, so that it makes little difference if thevents open downwardly, laterally, or even rearwardly of the speaker.

While I have shown and described certain specific embodiments of myinvention, it will be readily apparent that many minor changes ofstructure and operation could be made without departing from the spiritof the invention.

What I claim as new and desire to protect by Letters Patent is:

1. An outdoor speaker enclosure comprising:

a. a hollow box-like body member having a speaker opening formed in avertically extending wall thereof, said body member being adapted tohave a speaker mounted therein so as to direct sound outwardly throughsaid speaker opening, and

b. a protective panel secured to the outer surface of the body memberwall in which said speaker opening is formed, and overlying saidopening, said panel including a plurality of sheets of air-permeablefabric disposed in parallel, spaced-apart relation with spacestherebetween, said panel having a drain opening formed therethrough atthe bottom of the space between a pair of adjacent fabric sheets, saiddrain opening providing for drainage, exteriorly of said body member, ofany moisture collecting between said adjacent fabric sheets of saidprotective panel.

2. The structure as recited in claim 1, wherein said body member has apair of vent holes formed therein and communicating respectively withupper and lower portions of the interior thereof.

3. The structure as recited in claim 2, wherein said vent holes opendownwardly exteriorly of said body member with respect to adjacentportions of said body member, whereby to inhibit the entry of moistureinto said body member through said holes.

4. The structure as recited in claim 2, with the addition of a pair oftubes disposed within said body member each with one end higher than theother, the lower end of each of said tubes communicating with one ofsaid vent holes, with its upper end opening into the interior of saidbody member.

5. The structure as recited in claim 2, wherein said vent holes openthrough the vertically extending wall of said body member in which saidspeaker opening is formed, said protective panel which overlies saidspeaker opening also overlying said vent holes.

6. The structure as recited in claim 1 wherein the outer fabric sheet ofsaid penal is of relatively tough, coarse fabric through which water maypass relatively easily, and wherein said panel includes a plurality ofinner sheets of a relatively closely woven fabric through which watermay pass only with relative difficulty, the drain opening of said panelbeing disposed between a pair of said inner sheets.

7, The structure as recited in claim 6 wherein said protective panelincludes two of said relatively closely woven inner fabric sheets, andwherein said drain opening is disposed between said two inner sheets.

8. The structure as recited in claim 6 wherein said protective panelincludes an open frame with said fabric sheets overlying the openingthereof, wherein said drain opening is formed through said frameintermediate said two inner sheets, and wherein the edge of said framedefining the bottom of the space between said outer fabric sheet and theadjacent inner sheet is inclined downwardly toward said outer sheet.

1. An outdoor speaker enclosure comprising: a. a hollow box-like bodymember having a speaker opening Formed in a vertically extending wallthereof, said body member being adapted to have a speaker mountedtherein so as to direct sound outwardly through said speaker opening,and b. a protective panel secured to the outer surface of the bodymember wall in which said speaker opening is formed, and overlying saidopening, said panel including a plurality of sheets of air-permeablefabric disposed in parallel, spacedapart relation with spacestherebetween, said panel having a drain opening formed therethrough atthe bottom of the space between a pair of adjacent fabric sheets, saiddrain opening providing for drainage, exteriorly of said body member, ofany moisture collecting between said adjacent fabric sheets of saidprotective panel.
 2. The structure as recited in claim 1, wherein saidbody member has a pair of vent holes formed therein and communicatingrespectively with upper and lower portions of the interior thereof. 3.The structure as recited in claim 2, wherein said vent holes opendownwardly exteriorly of said body member with respect to adjacentportions of said body member, whereby to inhibit the entry of moistureinto said body member through said holes.
 4. The structure as recited inclaim 2, with the addition of a pair of tubes disposed within said bodymember each with one end higher than the other, the lower end of each ofsaid tubes communicating with one of said vent holes, with its upper endopening into the interior of said body member.
 5. The structure asrecited in claim 2, wherein said vent holes open through the verticallyextending wall of said body member in which said speaker opening isformed, said protective panel which overlies said speaker opening alsooverlying said vent holes.
 6. The structure as recited in claim 1wherein the outer fabric sheet of said penal is of relatively tough,coarse fabric through which water may pass relatively easily, andwherein said panel includes a plurality of inner sheets of a relativelyclosely woven fabric through which water may pass only with relativedifficulty, the drain opening of said panel being disposed between apair of said inner sheets. 7, The structure as recited in claim 6wherein said protective panel includes two of said relatively closelywoven inner fabric sheets, and wherein said drain opening is disposedbetween said two inner sheets.
 8. The structure as recited in claim 6wherein said protective panel includes an open frame with said fabricsheets overlying the opening thereof, wherein said drain opening isformed through said frame intermediate said two inner sheets, andwherein the edge of said frame defining the bottom of the space betweensaid outer fabric sheet and the adjacent inner sheet is inclineddownwardly toward said outer sheet.